Abuja  - Unknown gunmen have abducted Israeli citizen Ehud Arny from his residence in Port Harcourt in Nigeria's restive Niger Delta, police said Wednesday.

Police spokesperson Rita Abbey told Deutsche Presse-Agentur dpa that Arny, a project manager at Gilmore Construction Company, was abducted Tuesday night.

"We have started an investigation into the incident, but no militant group in the Niger Delta has claimed responsibility for the kidnap and no ransom demand has been made," she said.

Police have arrested Arny's Nigerian driver on suspicion of complicity in the abduction.

Militant groups frequently abduct expatriate workers in the Niger Delta, ostensibly to back their demands for a bigger share of oil profits from the oil-rich, but highly impoverished region.

The assailants usually release their captives after collecting a ransom, although employers and governments generally deny having paid. (dpa)